Balance Sheet Components - Property and Equipment, net (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 96,264,000		$ 96,264,000		$ 88,516,000
Less: accumulated depreciation	(23,086,000)		(23,086,000)		(16,958,000)
Property and equipment, net	73,178,000		73,178,000		71,558,000
Depreciation	3,300,000	$ 2,400,000	6,200,000	$ 4,700,000
Equipment and machinery
Property, Plant and Equipment [Line Items]
Property and equipment, gross	21,977,000		21,977,000		18,265,000
Computer hardware and software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	10,484,000		10,484,000		7,772,000
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,837,000		1,837,000		1,373,000
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	23,511,000		23,511,000		19,420,000
Building
Property, Plant and Equipment [Line Items]
Property and equipment, gross	35,154,000		35,154,000		35,154,000
Construction-in-process
Property, Plant and Equipment [Line Items]
Property and equipment, gross	3,301,000		3,301,000		6,532,000
Building and improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	53,400,000		53,400,000		$ 53,400,000
Line of Credit | Letter of Credit
Property, Plant and Equipment [Line Items]
Letter of credit	$ 4,000,000		$ 4,000,000